Boosted Redox Kinetics Enabling Na3V2(PO4)3 with Excellent Performance at Low Temperature through Cation Substitution and Multiwalled Carbon Nanotube Cross-Linking

Jiabao Li; Quan Yuan; Jingjing Hao; Ruoxing Wang; Tianyi Wang; Likun Pan; Junfeng Li; Chengyin Wang

doi:10.1021/acs.inorgchem.3c02457

Boosted Redox Kinetics Enabling Na₃V₂(PO₄)₃ with Excellent Performance at Low Temperature through Cation Substitution and Multiwalled Carbon Nanotube Cross-Linking

Inorg Chem. 2023 Oct 30;62(43):17745-17755. doi: 10.1021/acs.inorgchem.3c02457. Epub 2023 Oct 19.

Authors

Jiabao Li¹, Quan Yuan¹, Jingjing Hao¹, Ruoxing Wang¹, Tianyi Wang¹, Likun Pan², Junfeng Li³, Chengyin Wang¹

Affiliations

¹ School of Chemistry and Chemical Engineering, Yangzhou University, 180 Si-Wang-Ting Road, Yangzhou, Jiangsu 225002, China.
² Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Electronic Science, East China Normal University, No. 500 Dongchuan Road, Shanghai 200241, China.
³ College of Logistics Engineering, Shanghai Maritime University, Shanghai 201306, China.

PMID: 37856879
DOI: 10.1021/acs.inorgchem.3c02457

Abstract

The open NASICON framework and high reversible capacity enable Na₃V₂(PO₄)₃ (NVP) to be a highly promising cathode candidate for sodium-ion batteries (SIBs). Nevertheless, the unsatisfied cyclic stability and degraded rate capability at low temperatures due to sluggish ionic migration and poor conductivity become the main challenges. Herein, excellent sodium storage performance for the NVP cathode can be received by partial potassium (K) substitution and multiwalled carbon nanotube (MWCNT) cross-linking to modify the ionic diffusion and electronic conductivity. Consequently, the as-fabricated Na_3-xK_xV₂(PO₄)₃@C/MWCNT can maintain a capacity retention of 79.4% after 2000 cycles at 20 C. Moreover, the electrochemical tests at -20 °C manifest that the designed electrode can deliver 89.7, 73.5, and 64.8% charge of states, respectively, at 1, 2, and 3 C, accompanied with a capacity retention of 84.3% after 500 cycles at 20 C. Generally, the improved electronic conductivity and modified ionic diffusion kinetics resulting from K doping and MWCNT interconnecting endows the resultant Na_3-xK_xV₂(PO₄)₃@C/MWCNT with modified electrochemical polarization and improved redox reversibility, contributing to superior performance at low temperatures. Generally, this study highlights the potential of alien substitution and carbon hybridization to improve the NASICON-type cathodes toward high-performance SIBs, especially at low temperatures.